Malicious PDF — malware analysis report

Static analysis result for SHA-256 d21533e03ca4b762…

MALICIOUS

PDF

89.8 KB Created: 2021-07-22 18:04:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8648820deef60f4b91bdd52cd9f5cd75 SHA-1: 9f5c9fd8c9546e6d7417eb2342836415482f9cf4 SHA-256: d21533e03ca4b7621a31dc98ff64d26960f431b0a2785cbf57141a223bef07ba
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by ClamAV as a phishing trojan. It contains embedded JavaScript and a large number of external URIs, many pointing to compromised or disposable hosting, indicating a likely phishing or malicious redirection scheme. The presence of embedded JavaScript suggests an attempt to execute malicious code within the PDF viewer.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9913

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://iswii.net/ckfinder/userfiles/files/lalirijosuvajokipit.pdf
    • http://www.appsolutely.sg/wp-content/plugins/formcraft/file-upload/server/content/files/1606cf8a9d7d45---95340871602.pdf
    • http://socialbomjesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/16088bb76b0f5e---zedidogavikavemiretalopi.pdf
    • http://emanuelmlevin.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/lofarawerumiz.pdf
    • https://gearforfree.com/wp-content/plugins/super-forms/uploads/php/files/4fue5b6v9pubb1rmfbem2c7j1l/66989774852.pdf
    • http://pvvc.cz/files/44131612772.pdf
    • https://cursosadistanciayonline.com/medios//files/devuxup.pdf
    • http://vdgairconditioning.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160755c8a4e7ca---tuvenalusazopopokukigi.pdf
    • http://movitecnic.com/ressource/site-image/files/mezovukujofen.pdf
    • https://juniorclublivorno.com/sitonews/images_upload/files/31327786593.pdf
    • http://esoftland.com/userfiles/file/78663329885.pdf
    • http://parbatsamajjapan.com/img/files/files/befumavi.pdf
    • http://shsclassof1959.com/clients/a/a7/a7a82b2a6025f7fafce5d77be70bf845/File/22037635428.pdf
    • http://mgocsm.in/userfiles/file/jodiredobibigisudejivim.pdf
    • http://bestbuyfromindia.com/userfiles/file/botifefisa.pdf
    • http://remaining-mc.de/userfiles/file/nijilajuminobo.pdf
    • http://mrbossamktown.com/uploads/files/78881263640.pdf
    • https://proff-doors.ru/wp-content/plugins/super-forms/uploads/php/files/f9677701204cbbdfc72d52c9fc40b1a3/lekiz.pdf
    • http://gunjanjain.com/app/webroot/js/uploads/files/tasedonuwa.pdf
    • http://www.telsercom.com/wp-content/plugins/formcraft/file-upload/server/content/files/160778da25f2c0---61061913668.pdf
    • https://fresh-cherries.com/ckfinder/userfiles/files/6821234922.pdf
    • http://www.playerclub.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160abd9a636739---risumoterejojipebalikadu.pdf
    • https://valserve.in/web/k/main_admin/ckfinder/userfiles/files/40960229357.pdf
    • https://trungtammatnamviet.vn/upload/files/17573416873.pdf
    • http://aihyang.com/userfiles/file/46651935664.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=social+science+choose+the+correct+answer
    • http://e1pl2.nazwa.pl/busy/fotki/file/51228224006.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000fda5.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFDA5 16792 bytes
font_01_sfnt_off000115bc.bin
76dbe6cdfd7846fb3d6b5d34fd4c71fbe26e66edc7c1ca98f9a7036fd2b2b955
pdf-font-stream PDF embedded font (sfnt) at offset 0x115BC 10488 bytes
font_02_sfnt_off00012d85.bin
157da14cb177a753fbe6d60cd67112ba2c77b306a540ca9748c8794f0a5c0a2e
pdf-font-stream PDF embedded font (sfnt) at offset 0x12D85 17036 bytes